For about two hours on Tuesday, the Senate Natural Resources Committee discussed whether to tighten rules governing water wells used to supply hydraulic fracturing operations.

The discussion centered on Senate Bill 873, carried by state Sen. Glenn Hegar, R-Katy, which would allow local groundwater authorities to require oil and gas companies using water for fracking to get permits.

Hydraulic fracturing, or fracking, is a water-intensive operation that involves shooting roughly 4 million to 6 million gallons of water — or more — down a hole to break up rock and retrieve oil and gas. The water also contains sand and chemicals.

Many groundwater districts say Texas law is unclear about whether they can require frackers to get a permit for their water-supply wells. The law exempts water wells used for rigs' “drilling or exploration” operations from permitting requirements. But that language was written more than a decade ago, before the spread of fracking, and the legal debate centers on whether fracking falls into the categories of drilling and exploration.

Hegar said he simply is trying to clarify the law so groundwater districts could require the permits if they want to. He emphasized that his bill would not require districts to require permits.

A permit can create a limit on the amount of water used. Groundwater districts supported Hegar's bill, while oil and gas groups generally opposed it.

Teddy Carter, a representative of the Texas Independent Producers and Royalty Owners Association, said his “biggest worry” is the possibility that groundwater authorities would not be able to issue permits quickly, thus delaying drilling operations. “Some groundwater districts are pretty limited on their supply and staff,” he said.

State Sen. Robert Duncan, R-Lubbock, appeared interested in ending the “drilling or exploration” exemption in general. Farmers must obtain permits for water wells, he noted, so why shouldn't oil and gas companies be required to get permits too?

“Why would we grant an exemption to the oil and gas operation but not to the corn farmer?” Duncan asked. “What's the difference between the corn farmer and the oil company that's getting at least $80 a barrel? ... What's equitable about allowing some industries to have an exemption and not others?”

Hegar responded that the equity questions were valid and could merit further discussion, but his bill was focused on a narrower point.

State Sen. Troy Fraser, R-Horseshoe Bay, the committee chairman, appears to favor the bill. Senate Bill 332, which passed through the Legislature last session and was carried by Fraser, struck a delicate balance between declaring that landowners own the water that comes up from their ground, and yet allowing for continued groundwater district regulation.

“My legal advice is you're interpreting the law the wrong way, and that is not the intent of the Legislature,” Fraser told Cory Pomeroy, a representative of the Texas Oil and Gas Association, which opposes SB 873 and argues that oil and gas drillers are currently exempt from the groundwater districts' permitting requirements, even when it comes to water for fracking.

Mike Mahoney, the general manager of the Evergreen Groundwater Conservation District, a four-county district in the Eagle Ford Shale, said his district requires permits for fracking water wells and has had no difficulty with compliance.

“We are in no way doing anything that is preventing the oil companies from being able to drill the wells or to frack the wells,” he testified.